// Copyright (c) 2013 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifndef MEDIA_CAPTURE_VIDEO_VIDEO_CAPTURE_BUFFER_POOL_IMPL_H_
#define MEDIA_CAPTURE_VIDEO_VIDEO_CAPTURE_BUFFER_POOL_IMPL_H_

#include <stddef.h>

#include <map>

#include "base/files/file.h"
#include "base/macros.h"
#include "base/memory/ref_counted.h"
#include "base/memory/shared_memory.h"
#include "base/process/process.h"
#include "base/synchronization/lock.h"
#include "build/build_config.h"
#include "media/base/video_frame.h"
#include "media/capture/capture_export.h"
#include "media/capture/video/video_capture_buffer_handle.h"
#include "media/capture/video/video_capture_buffer_pool.h"
#include "media/capture/video/video_capture_buffer_tracker_factory.h"
#include "media/capture/video_capture_types.h"
#include "ui/gfx/geometry/size.h"
#include "ui/gfx/gpu_memory_buffer.h"

namespace media {

class CAPTURE_EXPORT VideoCaptureBufferPoolImpl
    : public VideoCaptureBufferPool {
public:
    explicit VideoCaptureBufferPoolImpl(
        std::unique_ptr<VideoCaptureBufferTrackerFactory> buffer_tracker_factory,
        int count);

    // VideoCaptureBufferPool implementation.
    mojo::ScopedSharedBufferHandle GetHandleForInterProcessTransit(
        int buffer_id) override;
    base::SharedMemoryHandle GetNonOwnedSharedMemoryHandleForLegacyIPC(
        int buffer_id) override;
    std::unique_ptr<VideoCaptureBufferHandle> GetHandleForInProcessAccess(
        int buffer_id) override;
    int ReserveForProducer(const gfx::Size& dimensions,
        media::VideoPixelFormat format,
        media::VideoPixelStorage storage,
        int frame_feedback_id,
        int* buffer_id_to_drop) override;
    void RelinquishProducerReservation(int buffer_id) override;
    int ResurrectLastForProducer(const gfx::Size& dimensions,
        media::VideoPixelFormat format,
        media::VideoPixelStorage storage) override;
    double GetBufferPoolUtilization() const override;
    void HoldForConsumers(int buffer_id, int num_clients) override;
    void RelinquishConsumerHold(int buffer_id, int num_clients) override;

private:
    friend class base::RefCountedThreadSafe<VideoCaptureBufferPoolImpl>;
    ~VideoCaptureBufferPoolImpl() override;

    int ReserveForProducerInternal(const gfx::Size& dimensions,
        media::VideoPixelFormat format,
        media::VideoPixelStorage storage,
        int frame_feedback_id,
        int* tracker_id_to_drop);

    VideoCaptureBufferTracker* GetTracker(int buffer_id);

    // The max number of buffers that the pool is allowed to have at any moment.
    const int count_;

    // Protects everything below it.
    mutable base::Lock lock_;

    // The ID of the next buffer.
    int next_buffer_id_;

    // The ID of the buffer last relinquished by the producer (a candidate for
    // resurrection).
    int last_relinquished_buffer_id_;

    // The buffers, indexed by the first parameter, a buffer id.
    std::map<int, std::unique_ptr<VideoCaptureBufferTracker>> trackers_;

    const std::unique_ptr<VideoCaptureBufferTrackerFactory>
        buffer_tracker_factory_;

    DISALLOW_IMPLICIT_CONSTRUCTORS(VideoCaptureBufferPoolImpl);
};

} // namespace media

#endif // MEDIA_CAPTURE_VIDEO_VIDEO_CAPTURE_BUFFER_POOL_IMPL_H_
